Film extrusion apparatus



P 7, 1955 A. o. RUSSELL FILM EXTRUSION APPARATUS 2 Sheets-Sheet 1 FiledJan. 23, 1952 t R Kw s Nm Q N wf N QM @N N A A m\ l R NM ya 0 m mN Q R aw w n hhw m Mm vn INVENTOR. ARTHUR O. RUSSELL Q T; iii; 1:

F: C E C p 27, 1955 A. o. RUSSELL 2,718,661

FILM EXTRUSION APPARATUS Filed Jan. 25, 1952 2 Sheets-Sheet 2 UnitedStates Patet1f FEM EXTRUSION APPARA US.

Arthur-l0. Russell, Fredericksburg va assignor to American ViscoseCorporatiomtwilmington, -Del'.,: a corpo- -t ration of Delaware pp on uy Z,. ria! ND-.2.67,840

7 Claims. (Cl. 18-:-:-15) .1

This invention relates toapparatus for producing non;v

fibrous foils, pellicles filrns,r,,sheetsv and like products fromfilm-forming compositiens. v More particularly it H relates to animproved\extrusiondevice whichprovides greater adjustability and controlof. the ultin atei thick ness of the extruded film..

The manufacture of films, foils and likeproductsis m y c r u i by X rudng.,i o-a c agulat n or regenerating bath a film-forming substance suchas viscose from a receptacle or hopper which is provided with slightlyseparated lips that define an elongated oridemands of production oftenrequire that the width ofthe orifice amount to only a fraction ofarnilljneter.

Although various previous improvements have. been sug-... gested toovercomethisdifiiculty theyhave .beenshown unable to provide suflicientaccuracy in controlling. the,

required dimensions of the orifice. s

It is a principal object of this invention to provide,

novel and improved film extrusion apparatus wherein,

the dimensions of the elongatedextrusion.orificeamay be quickly andaccurately adjusted...

It is a further object of this. invention toconveniently,..

position the extrusion orifice adjusting means suchtthatt it may beeasily reached and-manipulated.

Referring .now more particularly tozFigures 1,,2 and.3 of. .the.drawing, the spinninghead assembly 3.,is rotat-. ably mounted by meansof the tubulantrunnions 6 in the. journals v,4 whichare positioned atopposite ends of the coagulating \vessel or..container 5.. The hand.wheel; 7 in, ,Fig ure.1 .of the, drawing. provides a convenient meansfor rotatably .adjusting..,thev position .of-.the..spin-.. niugassembly. in the .journals..4 to control the angular-- disposition ofthe spinning ,orifice in the.coagulating-1. vessel .or chamber.and.;toinver.t the assembly .forzthe inspection .and maintenancethereof.

The. spinning assembly 3.,comprises a pair ofelongated. U-shaped channelmembers. .8 .and ,9 which are fastened, back to back by, the bolts \10.Cover plates 11 andZ'L extend .acrossthe opensides andsends.respectively.,of thephanrrelv members 8 and 9 and:providebetweenwuit:able, inlet-and discharge means not shown ;in, .the. drawing theelongated, enclosedchambers 12 .and. 13 through... which may I flow atemperature regulating. medium -such aslwater steam or air.. The lowerportions of the .abutting channel. members 8rand 9 are preferablyrecessed. as shown 1 in the, drawing to form the. channel. 26...therebetween but;.it,is,to be understood that.the..channel maybeformed; in any convenient other way such as by insert-. r ing-a shim 1between, theupper portions. of the abutting chann lm mb r Carried. ,.on.th ejunderside..of the. channel members 8 .v and) are the, adjustable.lip .members ,14 and. 15 which. determine the .width oftheextrusionnorificer Eachof the rlip membersv includes in.,cross-section. .a lip proper. 41 which is. formed. integrally. .with a horizontal.fiange, or,-,extensi on at an angle thereto. As shown in Figures 5and,.6,. the. extension lies in a horizontal plane hflffias ,thelip.proper 41;;extends downwardly.- and, obliquely. The extension .40.-oflip member 14 is fas-.

. tenedto the, lowensurface, of bearing plate .16 .andchan- Otherobjects and advantages of the invention will be-..;.

come apparent from a description of .the of the invention.

by providing a pair of independent adjustingmeans; for

embodiments 1 each extrusion orifice.- The first .adjusting. meanS.-:P9-. vides a coarse control of the width of. the: orifice ,by

slidably adjusting the position :of;.the entire. lip member The secondadjusting means, provides a more delicate adjustment of the orificedimension .by means of. a flexing action of a lip member.

In the accompanying drawing which is illustrative ofz the invention,

Figure 1 is a front. view of a spinningheadassembly wherein there isdisclosedan improved extrusion lip v adjusting means which is designedin accordance. with a vview f t mprpv d .spinninglgeadm Figure 4 is across-sectional view of a modifie'tl spinning head assembly which isdesigned in'accordance .with a second embodiment of the invention;

Figure 5 isan enlarged fragmentary view similar, to

Figure 2 showing the adjustable lip member in a sub-1 stantially closedposition; and

Figure 6 is a view similar to Figure S in'which; the

adjustment achieved has been'illustrated in a somewhat;-

exaggerated manner.

nel r r1e m,ber,. 8 ,by; a plurality ofupwardly. extending. ,cap,.screws 17 which,;are located along; each of. its:elong-ated,. edges.The, extens.ion-.40 ,of the .lip..member-,15 .isifas. tened to,itsrespective-channel members 9 by a pluralityv I of cap screws 19,whichrextend upwardly. through .a pinrality of slots 18, in. the .lipmember, through .the assowciated bearingplate 20; and threadedly engagethe under: I side;p .,the channel. member.; The .slots 18 .in .the lipmember 15 permit-a transverse sliding adjustment ofthe lip;,member aswill ,bedescribed more fully, hereinaften.

The opposed .angularlips -41,.0f the..rorificertdefining lip mfimbersnfiand ,.15 ,are alined, with .channel'lti,v formed between thechannelmembers 8 and 9 and- :are preferably tapered downwardly. toward theextrusion ori-r: fice Thegupper boundary. or .walhof the channel 26.between the, channel members 8 and 9 is also preferablytapereddownwardly. fromthe end. of the spinning. assem-- bly at whichthe, spinning. solution is supplied toward the opposite end, thereof..Supporting .blocks. -28.:arebolted to the lowenp'ortion ofeach endaofthe channels members- .and extend downwardly therefrom. Each Of thesupporting; blocks carries. thetbolt means ,29ga1'ld' 30: for removably.clamping .the- .end. plates. 31.v across; the. end extrerrnjties of.the, opposing orifice defining 1ips Thus, it is seen that thespinning,solutionwmay progress-1 from its source not; shown .onthe-drawing through; the tubular trunnion'fi ,along the grooved-portionbetween the channel rnembers .and downwardly through therelon-a atedpifii e i to the-coag b Each of the lip m bers 14, and 15 is;designedv.such that it can be independently adjusted .to .control .-@thedimensions of the extrusionorifice. Lip,member.15..may,. be slidablypositioned in slots 18 .on cap ,screwst19. by, means of the adjustingscrews 21 -.whichr.,threadedly.en; gage the end. of extension 40 andextend eut dl therefrom: Supporting bracket member 32 which extendsoutwardly and downwardly from the cover plate 11 guides each adjustingscrew in slots 33 and cooperates with the adjustable nuts 34 and 35 onthe adjusting screws to control the position of the lip member on capscrews 19. This sliding adjustment of lip member 15 readily permits apreliminary coarse adjustment of the orifice dimensions.

The dimensions of the orifice may also be controlled by varying theposition of lip member 14. The means which has been devised forcontrolling the adjustability of lip member 14 includes a plurality ofadjusting screws 23 which are fastened along the center of the extensionof the elongated lip member and extend upwardly therefrom through thelegs of the channel member 8. Supporting bracket member 36 which ismounted on the upper surface of channel member 8 guides the upperportion of the adjusting screws in apertures 37 and cooperates with theadjustable nuts 38 and 39 on the adjusting screws to control theposition of the lip proper 41. Thus, variations in the setting ofadjusting screw 23 cause a bowing action within the elastic limit of themetal in the mounting portion of the relatively flexible extensionbetween the cap screws 17 and the angular portion simultaneously flexestoward or away from the opposing lip member 15. The adjustment describedabove results from a bending or flexing of the lip along a minor ortransverse axis thereof as opposed to a flexing longitudinally or alongthe major axis. It has been found that control of this type of flexingaction in the lip member provides a very accurate means for makingminute adjustments in the width of the orifice. The upper surface of thelip member 14 is preferably undercut at 24 between the axes of the capscrews 17 to provide greater flexibility of the lip member and a greaterrange of adjustability of the orifice dimensions.

An additional feature of the novel and improved orifice adjusting meansof the present invention is to be noted in the ready accessibility ofthe adjusting means in its conveniently exposed location.

Referring next to Figure 4 of the drawing a second embodiment of theinvention is disclosed wherein a pair of adjustably controlled orificespermit the simultaneous extrusion of a like number of non-fibrous films.In this embodiment of the invention the spinning head assembly isdivided into two separate chambers and 51 by a downwardly extendinginverted Y-shaped partition member 52. The lower portion 61 of the legsof the Y partition form a fixed lip member for each of the extrusionorifices. The opposing lip member 63 of each of the orifices isadjustably mounted by means of the cap screws 54 upon elongated U-shapedchannel members 58 which are fastened to the upper portion of thepartition member 52 by means of bolts 59. Each of the lip members 63includes in cross-section a mounting portion and an orifice-definingangular portion which extends downwardly therefrom. The open sides andends of the channel members are preferably respectively closed by theside plates 53 and end plates not shown in the drawing thereby providingelongated chambers through which a temperature regulating medium mayflow as described in the previously described embodiment. As in thepreviously described embodiment the opposed surfaces of the orificedefining lip members 63, 63 are alined with the chambers 50 and 51 andare preferably tapered downwardly toward the extrusion orifice.

Each of the movable lip members 63 may be slidably positionable in slotson cap screws 54 by means of the adjusting screw 55 which threadedlyengages the end of the mounting portion of lip member 63 and extendsoutwardly therefrom. Supporting bracket member 69 which extendsoutwardly from the cover plate 53 guides each adjusting screw in slots70 and cooperates with the adjustable nuts 71 and 72 on the adjustingscrews to control the position of the lip member on cap screws 54. Thissliding means permits a preliminary coarse 4 adjustment of the width ofeach of the orifices. The elongated adjusting screws 57 provide anadditional means for varying and controlling the dimensions of theorifice. The elongated adjusting screws are fastened to the center ofthe mounting portion of each of the elongated lip members 63 between thebolts 54 and extend upwardly therefrom through the legs of channelmember 58. Supporting brackets 73 which are mounted on the uppersurfaces of channel members 58 guide the upper portion of the adjustingscrews in apertures 74 and cooperate with the adjustable nuts 75 and 76on the adjusting screw to control the position of the lip member. Thus,variations in the setting of the adjusting screw 57 cause a bowingaction in the mounting portion of the relatively flexible lip members 63between the bolts 44 and the angular portion simultaneously flexestoward or away from the corresponding fixed lip member 61. As in thepreviously disclosed embodiment the upper surface of the lip member ispreferably undercut as at 77 to provide greater flexibility of the lipmember and a greater range of adjustability of the width of the orifice.

While preferred embodiments of the invention have been described, thedescription is intended to be illustrative only and it is to beunderstood that changes and variations may be made without departingfrom the spirit and scope of the invention as defined by the appendedclaims.

I claim:

1. Apparatus for defining and controlling the width of an extrusionorifice comprising a pair of opposed lip members, an integrally formedoblique extension on at least one of said lip members, and means forlowering said extension in a transverse plane to control the width ofthe orifice.

2. Film extrusion apparatus comprising a spinning head assembly havingan elongated opening therein, at least one lip secured to the spinninghead having a flange extending longitudinally of the spinning head andobliquely to the lip, and means for bending the flange to pivot the lipand thereby control the width of said opening.

3. Film extrusion apparatus comprising a spinning head assembly havingan elongated opening therein, at least one lip secured to the spinninghead having a flange extending longitudinally of the spinning head andobliquely to the lip, at least one adjusting screw extending through thespinning head and connected to said flange approximately at its center,and means for applying pressure to said screw to flex the flange toadjust the width of the opening.

4. Film extrusion apparatus comprising a spinning head assembly havingan elongated opening therein, a pair of opposed orifice defining lipmembers positioned on the assembly and which partially extend across thewidth of the opening, a lip proper formed along at least one of the lipmembers, at least one of the lip members having a flange extendingsubstantially at right angles to said lip proper, and means for bendingsaid flange to adjust the Width of the orifice.

5. Apparatus in accordance with claim 4 having a plurality of boltsextending through the head along the length of the flange.

6. Film extrusion apparatus comprising a spinning head assembly havingan elongated opening therein, a pair of L-shaped lip members secured tosaid spinning head, said members having a substantially horizontalextension and a lip proper formed integrally and obliquely therewith,the outer edges of said lips being positioned in close spacedrelationship to form an extrusion orifice therebetween, and means forbending the extension of one of said lip members to closely control thewidth of said orifice.

7. Film extrusion apparatus comprising a spinning head assembly havingan elongated opening therein, an L- shaped lip member extendinglongitudinally of the spinning head, a first fulcrumed edge along thebackface of the lip member, a second fulcrumed edge extending along thebackface of the lip member in spaced transverse relation to said firstedge, and means for bending the lip member between said fulcrums topivot the outer edge of 5 the lip through an are centered substantiallyat one fulcrum.

References Cited in the file of this patent UNITED STATES PATENTSKinsella et al. Jan. 7, Crane et a1 June 15, Fordyce Sept. 8, Fordyce eta1. Sept. 8,

Bailey et a1. Aug. 23,

1. APPARATUS FOR DEFINING AND CONTROLLING THE WIDTH OF AN EXTRUSIONORIFICE COMPRISING A PAIR OF OPPOSED LIP MEMBERS, AN INTEGRALLY FORMEDOBLIQUE EXTENSION ON AT LEAST ONE OF SAID LIP MEMBERS, AND MEANS FORLOWERING SAID EXTENSION IN A TRANSVERSE PLANE TO CONTROL THE WIDTH OFTHE ORIFICE.